{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,30]],"date-time":"2026-09-30T13:28:30Z","timestamp":1790774910360,"version":"4.1.0"},"reference-count":43,"publisher":"MDPI AG","issue":"15","license":[{"start":{"date-parts":[[2022,8,5]],"date-time":"2022-08-05T00:00:00Z","timestamp":1659657600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["JCM"],"abstract":"<jats:p>Exercise-induced increases in pulmonary blood flow normally increase pulmonary arterial pressure only minimally, largely due to a reserve of pulmonary capillaries that are available for recruitment to carry the flow. In pulmonary arterial hypertension, due to precapillary arteriolar obstruction, such recruitment is greatly reduced. In exercising pulmonary arterial hypertension patients, pulmonary arterial pressure remains high and may even increase further. Current pulmonary arterial hypertension therapies, acting principally as vasodilators, decrease calculated pulmonary vascular resistance by increasing pulmonary blood flow but have a minimal effect in lowering pulmonary arterial pressure and do not restore significant capillary recruitment. Novel pulmonary arterial hypertension therapies that have mainly antiproliferative properties are being developed to try and diminish proliferative cellular obstruction in precapillary arterioles. If effective, those agents should restore capillary recruitment and, during exercise testing, pulmonary arterial pressure should remain low despite increasing pulmonary blood flow. The effectiveness of every novel therapy for pulmonary arterial hypertension should be evaluated not only at rest, but with measurement of exercise pulmonary hemodynamics during clinical trials.<\/jats:p>","DOI":"10.3390\/jcm11154568","type":"journal-article","created":{"date-parts":[[2022,8,5]],"date-time":"2022-08-05T02:12:39Z","timestamp":1659665559000},"page":"4568","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":17,"title":["The Paradox of Pulmonary Vascular Resistance: Restoration of Pulmonary Capillary Recruitment as a Sine Qua Non for True Therapeutic Success in Pulmonary Arterial Hypertension"],"prefix":"10.3390","volume":"11","author":[{"given":"David","family":"Langleben","sequence":"first","affiliation":[{"name":"Center for Pulmonary Vascular Disease, Azrieli Heart Center and Lady Davis Research Institute, Jewish General Hospital, McGill University, Montreal, QC H3T 1E2, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Stylianos E.","family":"Orfanos","sequence":"additional","affiliation":[{"name":"1st Department of Critical Care and Pulmonary Services, Pulmonary Hypertension Center, Evangelismos Hospital, National and Kapodistrian University of Athens Medical School, 10676 Athens, Greece"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Benjamin D.","family":"Fox","sequence":"additional","affiliation":[{"name":"Pulmonary Division, Yitzchak Shamir Hospital, Tel Aviv University, Tzrifin 69978, Israel"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Nathan","family":"Messas","sequence":"additional","affiliation":[{"name":"Center for Pulmonary Vascular Disease, Azrieli Heart Center and Lady Davis Research Institute, Jewish General Hospital, McGill University, Montreal, QC H3T 1E2, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Michele","family":"Giovinazzo","sequence":"additional","affiliation":[{"name":"Center for Pulmonary Vascular Disease, Azrieli Heart Center and Lady Davis Research Institute, Jewish General Hospital, McGill University, Montreal, QC H3T 1E2, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5098-295X","authenticated-orcid":false,"given":"John D.","family":"Catravas","sequence":"additional","affiliation":[{"name":"Frank Reidy Research Center for Bioelectrics, Old Dominion University, Norfolk, VA 23529, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2022,8,5]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"10","DOI":"10.1172\/JCI101912","article-title":"Effect of exercise on cardiac output and pulmonary arterial pressure in normal persons and in patients with cardiovascular disease and pulmonary emphysema","volume":"27","author":"Hickam","year":"1948","journal-title":"J. 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